Pollution and lack of green spaces: increased risk of ADHD

New research by the Barcelona Institute for Global Health (ISGlobal) has found that children who are exposed to higher levels of pollution are 62% more likely to suffer from ADHD. The same study has also concluded that, on the contrary, greater exposure to green spaces reduces the risk of ADHD by 50%.

ADHD affects 5-10% of children and young people and is one of the most common neurodegenerative disorders. Therefore, the research team analysed data from 37,000 children in Canada and measured the percentage of vegetation in neighbourhoods, residential levels of NO₂ y PM_2,5 pollutants and noise levels. In doing so, they aimed to study the association between exposure to these environmental factors during early life and the later development of ADHD.

The results of the study showed that increased exposure to pollution led to an increased risk of ADHD. Specifically, every 2.1µg increase in PM_2,5 levels increased the risk of ADHD by 11%. The opposite association was observed for green spaces. A 12% increase in the percentage of vegetation resulted in a 10% reduction in the risk of ADHD. No association was found with the other environmental factors (NO₂ and noise).

“The results obtained should be taken into account for healthier urban planning.”

Matilda van den Bosch

Matilda van den Bosch, lead author of the study, explains that “there is an environmental inequality that means that children face a disproportionately higher risk”. She adds that “the associations we have found are modifiable. Therefore, the results should be taken into account for healthier urban planning“.

Additionally, another recent ISGlobal study of 300 Italian children has concluded that greater exposure to vegetation (i.e. living and studying near green areas) is associated with lower levels of oxidative stress.